ibss.c revision 5cff20e6c5a6591a79d3b027af222870f52bb550
1/* 2 * IBSS mode implementation 3 * Copyright 2003-2008, Jouni Malinen <j@w1.fi> 4 * Copyright 2004, Instant802 Networks, Inc. 5 * Copyright 2005, Devicescape Software, Inc. 6 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 7 * Copyright 2007, Michael Wu <flamingice@sourmilk.net> 8 * Copyright 2009, Johannes Berg <johannes@sipsolutions.net> 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13 */ 14 15#include <linux/delay.h> 16#include <linux/if_ether.h> 17#include <linux/skbuff.h> 18#include <linux/if_arp.h> 19#include <linux/etherdevice.h> 20#include <linux/rtnetlink.h> 21#include <net/mac80211.h> 22#include <asm/unaligned.h> 23 24#include "ieee80211_i.h" 25#include "driver-ops.h" 26#include "rate.h" 27 28#define IEEE80211_SCAN_INTERVAL (2 * HZ) 29#define IEEE80211_SCAN_INTERVAL_SLOW (15 * HZ) 30#define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ) 31 32#define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ) 33#define IEEE80211_IBSS_MERGE_DELAY 0x400000 34#define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ) 35 36#define IEEE80211_IBSS_MAX_STA_ENTRIES 128 37 38 39static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata, 40 struct ieee80211_mgmt *mgmt, 41 size_t len) 42{ 43 u16 auth_alg, auth_transaction, status_code; 44 45 if (len < 24 + 6) 46 return; 47 48 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg); 49 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction); 50 status_code = le16_to_cpu(mgmt->u.auth.status_code); 51 52 /* 53 * IEEE 802.11 standard does not require authentication in IBSS 54 * networks and most implementations do not seem to use it. 55 * However, try to reply to authentication attempts if someone 56 * has actually implemented this. 57 */ 58 if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1) 59 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0, 60 sdata->u.ibss.bssid, 0); 61} 62 63static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 64 const u8 *bssid, const int beacon_int, 65 struct ieee80211_channel *chan, 66 const size_t supp_rates_len, 67 const u8 *supp_rates, 68 const u16 capability, u64 tsf) 69{ 70 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 71 struct ieee80211_local *local = sdata->local; 72 int rates, i, j; 73 struct sk_buff *skb; 74 struct ieee80211_mgmt *mgmt; 75 u8 *pos; 76 struct ieee80211_supported_band *sband; 77 u32 bss_change; 78 79 80 /* Reset own TSF to allow time synchronization work. */ 81 drv_reset_tsf(local); 82 83 skb = ifibss->skb; 84 rcu_assign_pointer(ifibss->presp, NULL); 85 synchronize_rcu(); 86 skb->data = skb->head; 87 skb->len = 0; 88 skb_reset_tail_pointer(skb); 89 skb_reserve(skb, sdata->local->hw.extra_tx_headroom); 90 91 if (memcmp(ifibss->bssid, bssid, ETH_ALEN)) 92 sta_info_flush(sdata->local, sdata); 93 94 memcpy(ifibss->bssid, bssid, ETH_ALEN); 95 96 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; 97 98 local->oper_channel = chan; 99 local->oper_channel_type = NL80211_CHAN_NO_HT; 100 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); 101 102 sband = local->hw.wiphy->bands[chan->band]; 103 104 /* Build IBSS probe response */ 105 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon)); 106 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon)); 107 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 108 IEEE80211_STYPE_PROBE_RESP); 109 memset(mgmt->da, 0xff, ETH_ALEN); 110 memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN); 111 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN); 112 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int); 113 mgmt->u.beacon.timestamp = cpu_to_le64(tsf); 114 mgmt->u.beacon.capab_info = cpu_to_le16(capability); 115 116 pos = skb_put(skb, 2 + ifibss->ssid_len); 117 *pos++ = WLAN_EID_SSID; 118 *pos++ = ifibss->ssid_len; 119 memcpy(pos, ifibss->ssid, ifibss->ssid_len); 120 121 rates = supp_rates_len; 122 if (rates > 8) 123 rates = 8; 124 pos = skb_put(skb, 2 + rates); 125 *pos++ = WLAN_EID_SUPP_RATES; 126 *pos++ = rates; 127 memcpy(pos, supp_rates, rates); 128 129 if (sband->band == IEEE80211_BAND_2GHZ) { 130 pos = skb_put(skb, 2 + 1); 131 *pos++ = WLAN_EID_DS_PARAMS; 132 *pos++ = 1; 133 *pos++ = ieee80211_frequency_to_channel(chan->center_freq); 134 } 135 136 pos = skb_put(skb, 2 + 2); 137 *pos++ = WLAN_EID_IBSS_PARAMS; 138 *pos++ = 2; 139 /* FIX: set ATIM window based on scan results */ 140 *pos++ = 0; 141 *pos++ = 0; 142 143 if (supp_rates_len > 8) { 144 rates = supp_rates_len - 8; 145 pos = skb_put(skb, 2 + rates); 146 *pos++ = WLAN_EID_EXT_SUPP_RATES; 147 *pos++ = rates; 148 memcpy(pos, &supp_rates[8], rates); 149 } 150 151 if (ifibss->ie_len) 152 memcpy(skb_put(skb, ifibss->ie_len), 153 ifibss->ie, ifibss->ie_len); 154 155 rcu_assign_pointer(ifibss->presp, skb); 156 157 sdata->vif.bss_conf.beacon_int = beacon_int; 158 bss_change = BSS_CHANGED_BEACON_INT; 159 bss_change |= ieee80211_reset_erp_info(sdata); 160 bss_change |= BSS_CHANGED_BSSID; 161 bss_change |= BSS_CHANGED_BEACON; 162 bss_change |= BSS_CHANGED_BEACON_ENABLED; 163 ieee80211_bss_info_change_notify(sdata, bss_change); 164 165 rates = 0; 166 for (i = 0; i < supp_rates_len; i++) { 167 int bitrate = (supp_rates[i] & 0x7f) * 5; 168 for (j = 0; j < sband->n_bitrates; j++) 169 if (sband->bitrates[j].bitrate == bitrate) 170 rates |= BIT(j); 171 } 172 173 ieee80211_sta_def_wmm_params(sdata, supp_rates_len, supp_rates); 174 175 ifibss->state = IEEE80211_IBSS_MLME_JOINED; 176 mod_timer(&ifibss->timer, 177 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 178 179 cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel, 180 mgmt, skb->len, 0, GFP_KERNEL); 181 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL); 182} 183 184static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, 185 struct ieee80211_bss *bss) 186{ 187 u16 beacon_int = bss->cbss.beacon_interval; 188 189 if (beacon_int < 10) 190 beacon_int = 10; 191 192 __ieee80211_sta_join_ibss(sdata, bss->cbss.bssid, 193 beacon_int, 194 bss->cbss.channel, 195 bss->supp_rates_len, bss->supp_rates, 196 bss->cbss.capability, 197 bss->cbss.tsf); 198} 199 200static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata, 201 struct ieee80211_mgmt *mgmt, 202 size_t len, 203 struct ieee80211_rx_status *rx_status, 204 struct ieee802_11_elems *elems, 205 bool beacon) 206{ 207 struct ieee80211_local *local = sdata->local; 208 int freq; 209 struct ieee80211_bss *bss; 210 struct sta_info *sta; 211 struct ieee80211_channel *channel; 212 u64 beacon_timestamp, rx_timestamp; 213 u32 supp_rates = 0; 214 enum ieee80211_band band = rx_status->band; 215 216 if (elems->ds_params && elems->ds_params_len == 1) 217 freq = ieee80211_channel_to_frequency(elems->ds_params[0]); 218 else 219 freq = rx_status->freq; 220 221 channel = ieee80211_get_channel(local->hw.wiphy, freq); 222 223 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) 224 return; 225 226 if (sdata->vif.type == NL80211_IFTYPE_ADHOC && elems->supp_rates && 227 memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) { 228 supp_rates = ieee80211_sta_get_rates(local, elems, band); 229 230 rcu_read_lock(); 231 232 sta = sta_info_get(local, mgmt->sa); 233 if (sta) { 234 u32 prev_rates; 235 236 prev_rates = sta->sta.supp_rates[band]; 237 /* make sure mandatory rates are always added */ 238 sta->sta.supp_rates[band] = supp_rates | 239 ieee80211_mandatory_rates(local, band); 240 241#ifdef CONFIG_MAC80211_IBSS_DEBUG 242 if (sta->sta.supp_rates[band] != prev_rates) 243 printk(KERN_DEBUG "%s: updated supp_rates set " 244 "for %pM based on beacon info (0x%llx | " 245 "0x%llx -> 0x%llx)\n", 246 sdata->dev->name, 247 sta->sta.addr, 248 (unsigned long long) prev_rates, 249 (unsigned long long) supp_rates, 250 (unsigned long long) sta->sta.supp_rates[band]); 251#endif 252 } else 253 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates); 254 255 rcu_read_unlock(); 256 } 257 258 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems, 259 channel, beacon); 260 if (!bss) 261 return; 262 263 /* was just updated in ieee80211_bss_info_update */ 264 beacon_timestamp = bss->cbss.tsf; 265 266 /* check if we need to merge IBSS */ 267 268 /* merge only on beacons (???) */ 269 if (!beacon) 270 goto put_bss; 271 272 /* we use a fixed BSSID */ 273 if (sdata->u.ibss.bssid) 274 goto put_bss; 275 276 /* not an IBSS */ 277 if (!(bss->cbss.capability & WLAN_CAPABILITY_IBSS)) 278 goto put_bss; 279 280 /* different channel */ 281 if (bss->cbss.channel != local->oper_channel) 282 goto put_bss; 283 284 /* different SSID */ 285 if (elems->ssid_len != sdata->u.ibss.ssid_len || 286 memcmp(elems->ssid, sdata->u.ibss.ssid, 287 sdata->u.ibss.ssid_len)) 288 goto put_bss; 289 290 /* same BSSID */ 291 if (memcmp(bss->cbss.bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) 292 goto put_bss; 293 294 if (rx_status->flag & RX_FLAG_TSFT) { 295 /* 296 * For correct IBSS merging we need mactime; since mactime is 297 * defined as the time the first data symbol of the frame hits 298 * the PHY, and the timestamp of the beacon is defined as "the 299 * time that the data symbol containing the first bit of the 300 * timestamp is transmitted to the PHY plus the transmitting 301 * STA's delays through its local PHY from the MAC-PHY 302 * interface to its interface with the WM" (802.11 11.1.2) 303 * - equals the time this bit arrives at the receiver - we have 304 * to take into account the offset between the two. 305 * 306 * E.g. at 1 MBit that means mactime is 192 usec earlier 307 * (=24 bytes * 8 usecs/byte) than the beacon timestamp. 308 */ 309 int rate; 310 311 if (rx_status->flag & RX_FLAG_HT) 312 rate = 65; /* TODO: HT rates */ 313 else 314 rate = local->hw.wiphy->bands[band]-> 315 bitrates[rx_status->rate_idx].bitrate; 316 317 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate); 318 } else { 319 /* 320 * second best option: get current TSF 321 * (will return -1 if not supported) 322 */ 323 rx_timestamp = drv_get_tsf(local); 324 } 325 326#ifdef CONFIG_MAC80211_IBSS_DEBUG 327 printk(KERN_DEBUG "RX beacon SA=%pM BSSID=" 328 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n", 329 mgmt->sa, mgmt->bssid, 330 (unsigned long long)rx_timestamp, 331 (unsigned long long)beacon_timestamp, 332 (unsigned long long)(rx_timestamp - beacon_timestamp), 333 jiffies); 334#endif 335 336 /* give slow hardware some time to do the TSF sync */ 337 if (rx_timestamp < IEEE80211_IBSS_MERGE_DELAY) 338 goto put_bss; 339 340 if (beacon_timestamp > rx_timestamp) { 341#ifdef CONFIG_MAC80211_IBSS_DEBUG 342 printk(KERN_DEBUG "%s: beacon TSF higher than " 343 "local TSF - IBSS merge with BSSID %pM\n", 344 sdata->dev->name, mgmt->bssid); 345#endif 346 ieee80211_sta_join_ibss(sdata, bss); 347 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates); 348 } 349 350 put_bss: 351 ieee80211_rx_bss_put(local, bss); 352} 353 354/* 355 * Add a new IBSS station, will also be called by the RX code when, 356 * in IBSS mode, receiving a frame from a yet-unknown station, hence 357 * must be callable in atomic context. 358 */ 359struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, 360 u8 *bssid,u8 *addr, u32 supp_rates) 361{ 362 struct ieee80211_local *local = sdata->local; 363 struct sta_info *sta; 364 int band = local->hw.conf.channel->band; 365 366 /* 367 * XXX: Consider removing the least recently used entry and 368 * allow new one to be added. 369 */ 370 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) { 371 if (net_ratelimit()) 372 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n", 373 sdata->dev->name, addr); 374 return NULL; 375 } 376 377 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) 378 return NULL; 379 380#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 381 printk(KERN_DEBUG "%s: Adding new IBSS station %pM (dev=%s)\n", 382 wiphy_name(local->hw.wiphy), addr, sdata->dev->name); 383#endif 384 385 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 386 if (!sta) 387 return NULL; 388 389 set_sta_flags(sta, WLAN_STA_AUTHORIZED); 390 391 /* make sure mandatory rates are always added */ 392 sta->sta.supp_rates[band] = supp_rates | 393 ieee80211_mandatory_rates(local, band); 394 395 rate_control_rate_init(sta); 396 397 if (sta_info_insert(sta)) 398 return NULL; 399 400 return sta; 401} 402 403static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata) 404{ 405 struct ieee80211_local *local = sdata->local; 406 int active = 0; 407 struct sta_info *sta; 408 409 rcu_read_lock(); 410 411 list_for_each_entry_rcu(sta, &local->sta_list, list) { 412 if (sta->sdata == sdata && 413 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL, 414 jiffies)) { 415 active++; 416 break; 417 } 418 } 419 420 rcu_read_unlock(); 421 422 return active; 423} 424 425 426static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata) 427{ 428 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 429 430 mod_timer(&ifibss->timer, 431 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 432 433 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT); 434 435 if (ieee80211_sta_active_ibss(sdata)) 436 return; 437 438 if (ifibss->fixed_channel) 439 return; 440 441 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other " 442 "IBSS networks with same SSID (merge)\n", sdata->dev->name); 443 444 ieee80211_request_internal_scan(sdata, ifibss->ssid, ifibss->ssid_len); 445} 446 447static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata) 448{ 449 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 450 struct ieee80211_local *local = sdata->local; 451 struct ieee80211_supported_band *sband; 452 u8 *pos; 453 u8 bssid[ETH_ALEN]; 454 u8 supp_rates[IEEE80211_MAX_SUPP_RATES]; 455 u16 capability; 456 int i; 457 458 if (ifibss->fixed_bssid) { 459 memcpy(bssid, ifibss->bssid, ETH_ALEN); 460 } else { 461 /* Generate random, not broadcast, locally administered BSSID. Mix in 462 * own MAC address to make sure that devices that do not have proper 463 * random number generator get different BSSID. */ 464 get_random_bytes(bssid, ETH_ALEN); 465 for (i = 0; i < ETH_ALEN; i++) 466 bssid[i] ^= sdata->dev->dev_addr[i]; 467 bssid[0] &= ~0x01; 468 bssid[0] |= 0x02; 469 } 470 471 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n", 472 sdata->dev->name, bssid); 473 474 sband = local->hw.wiphy->bands[ifibss->channel->band]; 475 476 capability = WLAN_CAPABILITY_IBSS; 477 478 if (sdata->default_key) 479 capability |= WLAN_CAPABILITY_PRIVACY; 480 else 481 sdata->drop_unencrypted = 0; 482 483 pos = supp_rates; 484 for (i = 0; i < sband->n_bitrates; i++) { 485 int rate = sband->bitrates[i].bitrate; 486 *pos++ = (u8) (rate / 5); 487 } 488 489 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, 490 ifibss->channel, sband->n_bitrates, 491 supp_rates, capability, 0); 492} 493 494static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata) 495{ 496 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 497 struct ieee80211_local *local = sdata->local; 498 struct ieee80211_bss *bss; 499 struct ieee80211_channel *chan = NULL; 500 const u8 *bssid = NULL; 501 int active_ibss; 502 503 active_ibss = ieee80211_sta_active_ibss(sdata); 504#ifdef CONFIG_MAC80211_IBSS_DEBUG 505 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n", 506 sdata->dev->name, active_ibss); 507#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 508 509 if (active_ibss) 510 return; 511 512 if (ifibss->fixed_bssid) 513 bssid = ifibss->bssid; 514 if (ifibss->fixed_channel) 515 chan = ifibss->channel; 516 if (!is_zero_ether_addr(ifibss->bssid)) 517 bssid = ifibss->bssid; 518 bss = (void *)cfg80211_get_bss(local->hw.wiphy, chan, bssid, 519 ifibss->ssid, ifibss->ssid_len, 520 WLAN_CAPABILITY_IBSS, 521 WLAN_CAPABILITY_IBSS); 522 523#ifdef CONFIG_MAC80211_IBSS_DEBUG 524 if (bss) 525 printk(KERN_DEBUG " sta_find_ibss: selected %pM current " 526 "%pM\n", bss->cbss.bssid, ifibss->bssid); 527#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 528 529 if (bss && memcmp(ifibss->bssid, bss->cbss.bssid, ETH_ALEN)) { 530 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM" 531 " based on configured SSID\n", 532 sdata->dev->name, bss->cbss.bssid); 533 534 ieee80211_sta_join_ibss(sdata, bss); 535 ieee80211_rx_bss_put(local, bss); 536 return; 537 } else if (bss) 538 ieee80211_rx_bss_put(local, bss); 539 540#ifdef CONFIG_MAC80211_IBSS_DEBUG 541 printk(KERN_DEBUG " did not try to join ibss\n"); 542#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 543 544 /* Selected IBSS not found in current scan results - try to scan */ 545 if (ifibss->state == IEEE80211_IBSS_MLME_JOINED && 546 !ieee80211_sta_active_ibss(sdata)) { 547 mod_timer(&ifibss->timer, 548 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); 549 } else if (time_after(jiffies, ifibss->last_scan_completed + 550 IEEE80211_SCAN_INTERVAL)) { 551 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to " 552 "join\n", sdata->dev->name); 553 554 ieee80211_request_internal_scan(sdata, ifibss->ssid, 555 ifibss->ssid_len); 556 } else if (ifibss->state != IEEE80211_IBSS_MLME_JOINED) { 557 int interval = IEEE80211_SCAN_INTERVAL; 558 559 if (time_after(jiffies, ifibss->ibss_join_req + 560 IEEE80211_IBSS_JOIN_TIMEOUT)) { 561 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) { 562 ieee80211_sta_create_ibss(sdata); 563 return; 564 } 565 printk(KERN_DEBUG "%s: IBSS not allowed on" 566 " %d MHz\n", sdata->dev->name, 567 local->hw.conf.channel->center_freq); 568 569 /* No IBSS found - decrease scan interval and continue 570 * scanning. */ 571 interval = IEEE80211_SCAN_INTERVAL_SLOW; 572 } 573 574 ifibss->state = IEEE80211_IBSS_MLME_SEARCH; 575 mod_timer(&ifibss->timer, 576 round_jiffies(jiffies + interval)); 577 } 578} 579 580static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata, 581 struct ieee80211_mgmt *mgmt, 582 size_t len) 583{ 584 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 585 struct ieee80211_local *local = sdata->local; 586 int tx_last_beacon; 587 struct sk_buff *skb; 588 struct ieee80211_mgmt *resp; 589 u8 *pos, *end; 590 591 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || 592 len < 24 + 2 || !ifibss->presp) 593 return; 594 595 tx_last_beacon = drv_tx_last_beacon(local); 596 597#ifdef CONFIG_MAC80211_IBSS_DEBUG 598 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM" 599 " (tx_last_beacon=%d)\n", 600 sdata->dev->name, mgmt->sa, mgmt->da, 601 mgmt->bssid, tx_last_beacon); 602#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 603 604 if (!tx_last_beacon) 605 return; 606 607 if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 && 608 memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0) 609 return; 610 611 end = ((u8 *) mgmt) + len; 612 pos = mgmt->u.probe_req.variable; 613 if (pos[0] != WLAN_EID_SSID || 614 pos + 2 + pos[1] > end) { 615#ifdef CONFIG_MAC80211_IBSS_DEBUG 616 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq " 617 "from %pM\n", 618 sdata->dev->name, mgmt->sa); 619#endif 620 return; 621 } 622 if (pos[1] != 0 && 623 (pos[1] != ifibss->ssid_len || 624 !memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) { 625 /* Ignore ProbeReq for foreign SSID */ 626 return; 627 } 628 629 /* Reply with ProbeResp */ 630 skb = skb_copy(ifibss->presp, GFP_KERNEL); 631 if (!skb) 632 return; 633 634 resp = (struct ieee80211_mgmt *) skb->data; 635 memcpy(resp->da, mgmt->sa, ETH_ALEN); 636#ifdef CONFIG_MAC80211_IBSS_DEBUG 637 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n", 638 sdata->dev->name, resp->da); 639#endif /* CONFIG_MAC80211_IBSS_DEBUG */ 640 ieee80211_tx_skb(sdata, skb, 0); 641} 642 643static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata, 644 struct ieee80211_mgmt *mgmt, 645 size_t len, 646 struct ieee80211_rx_status *rx_status) 647{ 648 size_t baselen; 649 struct ieee802_11_elems elems; 650 651 if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN)) 652 return; /* ignore ProbeResp to foreign address */ 653 654 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; 655 if (baselen > len) 656 return; 657 658 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, 659 &elems); 660 661 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false); 662} 663 664static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, 665 struct ieee80211_mgmt *mgmt, 666 size_t len, 667 struct ieee80211_rx_status *rx_status) 668{ 669 size_t baselen; 670 struct ieee802_11_elems elems; 671 672 /* Process beacon from the current BSS */ 673 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt; 674 if (baselen > len) 675 return; 676 677 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems); 678 679 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true); 680} 681 682static void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata, 683 struct sk_buff *skb) 684{ 685 struct ieee80211_rx_status *rx_status; 686 struct ieee80211_mgmt *mgmt; 687 u16 fc; 688 689 rx_status = (struct ieee80211_rx_status *) skb->cb; 690 mgmt = (struct ieee80211_mgmt *) skb->data; 691 fc = le16_to_cpu(mgmt->frame_control); 692 693 switch (fc & IEEE80211_FCTL_STYPE) { 694 case IEEE80211_STYPE_PROBE_REQ: 695 ieee80211_rx_mgmt_probe_req(sdata, mgmt, skb->len); 696 break; 697 case IEEE80211_STYPE_PROBE_RESP: 698 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len, 699 rx_status); 700 break; 701 case IEEE80211_STYPE_BEACON: 702 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len, 703 rx_status); 704 break; 705 case IEEE80211_STYPE_AUTH: 706 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); 707 break; 708 } 709 710 kfree_skb(skb); 711} 712 713static void ieee80211_ibss_work(struct work_struct *work) 714{ 715 struct ieee80211_sub_if_data *sdata = 716 container_of(work, struct ieee80211_sub_if_data, u.ibss.work); 717 struct ieee80211_local *local = sdata->local; 718 struct ieee80211_if_ibss *ifibss; 719 struct sk_buff *skb; 720 721 if (!netif_running(sdata->dev)) 722 return; 723 724 if (local->sw_scanning || local->hw_scanning) 725 return; 726 727 if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_ADHOC)) 728 return; 729 ifibss = &sdata->u.ibss; 730 731 while ((skb = skb_dequeue(&ifibss->skb_queue))) 732 ieee80211_ibss_rx_queued_mgmt(sdata, skb); 733 734 if (!test_and_clear_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request)) 735 return; 736 737 switch (ifibss->state) { 738 case IEEE80211_IBSS_MLME_SEARCH: 739 ieee80211_sta_find_ibss(sdata); 740 break; 741 case IEEE80211_IBSS_MLME_JOINED: 742 ieee80211_sta_merge_ibss(sdata); 743 break; 744 default: 745 WARN_ON(1); 746 break; 747 } 748} 749 750static void ieee80211_ibss_timer(unsigned long data) 751{ 752 struct ieee80211_sub_if_data *sdata = 753 (struct ieee80211_sub_if_data *) data; 754 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 755 struct ieee80211_local *local = sdata->local; 756 757 set_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request); 758 queue_work(local->hw.workqueue, &ifibss->work); 759} 760 761void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) 762{ 763 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; 764 765 INIT_WORK(&ifibss->work, ieee80211_ibss_work); 766 setup_timer(&ifibss->timer, ieee80211_ibss_timer, 767 (unsigned long) sdata); 768 skb_queue_head_init(&ifibss->skb_queue); 769} 770 771/* scan finished notification */ 772void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local) 773{ 774 struct ieee80211_sub_if_data *sdata; 775 776 mutex_lock(&local->iflist_mtx); 777 list_for_each_entry(sdata, &local->interfaces, list) { 778 if (!netif_running(sdata->dev)) 779 continue; 780 if (sdata->vif.type != NL80211_IFTYPE_ADHOC) 781 continue; 782 if (!sdata->u.ibss.ssid_len) 783 continue; 784 sdata->u.ibss.last_scan_completed = jiffies; 785 ieee80211_sta_find_ibss(sdata); 786 } 787 mutex_unlock(&local->iflist_mtx); 788} 789 790ieee80211_rx_result 791ieee80211_ibss_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb, 792 struct ieee80211_rx_status *rx_status) 793{ 794 struct ieee80211_local *local = sdata->local; 795 struct ieee80211_mgmt *mgmt; 796 u16 fc; 797 798 if (skb->len < 24) 799 return RX_DROP_MONITOR; 800 801 mgmt = (struct ieee80211_mgmt *) skb->data; 802 fc = le16_to_cpu(mgmt->frame_control); 803 804 switch (fc & IEEE80211_FCTL_STYPE) { 805 case IEEE80211_STYPE_PROBE_RESP: 806 case IEEE80211_STYPE_BEACON: 807 memcpy(skb->cb, rx_status, sizeof(*rx_status)); 808 case IEEE80211_STYPE_PROBE_REQ: 809 case IEEE80211_STYPE_AUTH: 810 skb_queue_tail(&sdata->u.ibss.skb_queue, skb); 811 queue_work(local->hw.workqueue, &sdata->u.ibss.work); 812 return RX_QUEUED; 813 } 814 815 return RX_DROP_MONITOR; 816} 817 818int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, 819 struct cfg80211_ibss_params *params) 820{ 821 struct sk_buff *skb; 822 823 if (params->bssid) { 824 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN); 825 sdata->u.ibss.fixed_bssid = true; 826 } else 827 sdata->u.ibss.fixed_bssid = false; 828 829 sdata->vif.bss_conf.beacon_int = params->beacon_interval; 830 831 sdata->u.ibss.channel = params->channel; 832 sdata->u.ibss.fixed_channel = params->channel_fixed; 833 834 if (params->ie) { 835 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len, 836 GFP_KERNEL); 837 if (sdata->u.ibss.ie) 838 sdata->u.ibss.ie_len = params->ie_len; 839 } 840 841 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom + 842 36 /* bitrates */ + 843 34 /* SSID */ + 844 3 /* DS params */ + 845 4 /* IBSS params */ + 846 params->ie_len); 847 if (!skb) 848 return -ENOMEM; 849 850 sdata->u.ibss.skb = skb; 851 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; 852 sdata->u.ibss.ibss_join_req = jiffies; 853 854 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN); 855 856 /* 857 * The ssid_len setting below is used to see whether 858 * we are active, and we need all other settings 859 * before that may get visible. 860 */ 861 mb(); 862 863 sdata->u.ibss.ssid_len = params->ssid_len; 864 865 ieee80211_recalc_idle(sdata->local); 866 867 set_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 868 queue_work(sdata->local->hw.workqueue, &sdata->u.ibss.work); 869 870 return 0; 871} 872 873int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) 874{ 875 struct sk_buff *skb; 876 877 del_timer_sync(&sdata->u.ibss.timer); 878 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 879 cancel_work_sync(&sdata->u.ibss.work); 880 clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request); 881 882 sta_info_flush(sdata->local, sdata); 883 884 /* remove beacon */ 885 kfree(sdata->u.ibss.ie); 886 skb = sdata->u.ibss.presp; 887 rcu_assign_pointer(sdata->u.ibss.presp, NULL); 888 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED); 889 synchronize_rcu(); 890 kfree_skb(skb); 891 892 skb_queue_purge(&sdata->u.ibss.skb_queue); 893 memset(sdata->u.ibss.bssid, 0, ETH_ALEN); 894 sdata->u.ibss.ssid_len = 0; 895 896 ieee80211_recalc_idle(sdata->local); 897 898 return 0; 899} 900